A centralized laboratory is required to provide and maintain cells for each of the four projects in the Program. This core facility also will assist in the development of new approaches and procedures involving cell culture. There are ten specific aims: 1) Grow cells required for the experiments planned by the research projects, 2) passage active cultures and maintain frozen stocks, 3) Prepare, sterilize and test culture media, and maintain quality control, 4) Procure, initiate and maintain new cell lines requested by program investigators, 5) Prepare primary cultures of human umbilical vein endothelial cells and maintain them for two passages, 6) Grow endothelial cells on micropore filters and microcarrier beads, 7) Prepare CaCo-2 cultures on micropore filters, 8) Train new program scientists in tissue culture techniques, and assist project investigators in the development of new cell culture approaches to research problems, 9) Review current literature and test new sera, media, growth factors, and extracellular matrixes to optimize the growth of cell lines used by the project investigators, and 10) Development new systems that will open up new areas of research for the program.